Jhamel, his sister, was on board Enterprise, and was able to communicate with Gareb. She told him the truth, and he felt guilty that he was forced to destroy so many ships, and to kill so many people. Jhamel appealed to him to end the violence. He had one drone ship attack the other, destroying both Romulan starships. He was executed in the process by the Romulan Valdore, but was telepathically comforted by his sister at the end. (ENT: "The Aenar")